In this paper, I argue that men should take primary responsibility for protecting against pregnancy. Male long-acting reversible contraceptives are currently in development, and, once approved, should be used as the standard method for avoiding pregnancy. Since women assume the risk of pregnancy when they engage in penis-in-vagina sex, men should do their utmost to ensure that their ejaculations are responsible, otherwise women shoulder a double burden of pregnancy risk plus contraceptive responsibility. Changing the expectations regarding responsibility for contraception would (...) render penis-in-vagina sex more equitable, and could lead to a shift in the discourse around abortion access. I describe the sex asymmetries of contraceptive responsibility and of pregnancy-related risk, and offer arguments in favour of men taking primary responsibility for contraception. My arguments centre on: analogies between contraception and vaccination, and unwanted pregnancy and disease; a veil-of-ignorance approach, in which I contend that if a person were not told their sex, they would find a society in which men were expected to acquire and use effective contraceptives the fairest arrangement for everyone. (shrink)